As one of the most important rhetorical methods,using synonym to avoid repetition has a long history,is also unique in form.

Using synonym to avoid repetition is the rhetoric or rhetoric phenomenon which choose or create synonymous forms in the parallel structure according to their needs.

This evolution has resulted in a sharp and consistent definition of competitive advantage, which partially solved the issue of tautology and enhan.

There are three approaches to settle the dispute on whether the principle of natural selection is a tautology: taking a skeptical attitude to the scientific status of the principle of natural selection;redefining the fitness and selection;giving up the received view of the structure scientific theory.

The article makes a thorough analysis of tautology through the investigation of a considerable amount of material of the same language and reaches the conclusion that it is an important figure of speech in linguistic expression.

Research on the Synonym-compounds of Nouns, Verbs and Adjectives in Zhuangzi;

From the perspective of the diachronic character, the disyllabic roots condensed by synonym-compounds have the characteristics of dividing explanation.

We think that “Songyi”(诵易) is the error-writing of “Songxi”(诵习), “Shunli”(顺理), “Kuayan”(夸严) and “Guancai”(观采) are the synonym-compound, “Jicha”(纪 差) is a word on ancient calendar.

The lexicalization of "yijing" was the synonymy compound of "yi" and "jing".